mater.scichina.com link.springer.com . . . . . . . . . . . . . . . . . . Published online 19 September 2018 | https://doi.org/10.1007/s40843-018-9345-3Sci China Mater 2019, 62(4): 536–544
A stable ZIF-8-coated mesh membrane with micro-/nano architectures produced by a facile fabricationmethod for high-efficiency oil-water separationMingqiu Song1, Yuxin Zhao2, Shanjun Mu2, Chunming Jiang2, Zhan Li1, Pingping Yang1,Qianrong Fang1, Ming Xue1* and Shilun Qiu1
ABSTRACT With the possibility of large-area processing, theZIF-8-coated mesh membranes with rough micro-/nanos-tructures and underwater superoleophobic properties weresuccessfully fabricated at ambient temperature and pressure.These membranes exhibited excellent separation efficiencyover 99.99% for various oil-water mixtures with the residualoil content in the collected water less than 4 ppm, and highwater flux of 10.2×104 L m−2 h−1. Furthermore, the ZIF-8-coated mesh membrane displayed outstanding stability to-wards high temperature and various organic solvents im-mersion. More importantly, based on its facile fabricationmethod, this kind of ZIF-8-coated mesh membrane can beeasily enlarged, which is critical for the practical oil-waterseparation applications.
INTRODUCTIONThe separation of oil and water has become an urgentglobal challenge owing to water pollution caused by fre-quent oil spillage events, and it is also necessary to re-move oil or fat from the water system for many industrialprocesses [1–3]. Currently implemented oil-water se-paration technologies include centrifugation, filtration,dissolved air flotation, distillation, oil skinners, adsorp-tion, and electrochemical methods, etc. [4–6]. Suchtechnologies are low efficiency and consume a lot of en-ergy during complex separation processes [7]. And someadsorption materials also have the drawbacks of theoleophilic materials and absorbed oil waste, and the sec-ondary pollution during the post-treatment process.
Therefore, due to the pressure of economic developmentand more stringent environmental control, application ofcost-effective and high efficient processes for oil andwater separation becomes more important [8].
Recently, membrane technologies have attracted in-creasing interest in the separation application as a pro-mising and economical approach [9–11]. Meshmembrane for separating oil-water mixture driven bycapillarity has been recognized as an effective way toachieve high flux and separation efficiency [12–16]. Somepolymers, such as polytetrafluoroethylene (PTFE), poly-dimethylsiloxane (PDMS) and poly(stearylmethacrylate)(PStMA) have been successfully applied on mesh mem-branes [17,18], however, owing to their oleophilic prop-erty, the surface of these membranes is easily polluted oreven blocked up by oil [19]. It is well known that thewetting behavior of the solid surfaces is mainly affectedby the geometrical structure and chemical composition[20,21]. We often use the contact angle (CA) given byYoung’s equation to assess the wettability of the solidsurface [22]. The Young’s equation is applicable to bothliquid droplets on solid surfaces in the air and liquiddroplets on solid surfaces under second liquid [23]. Par-ticularly, the Cassie state can be realized under solid/water/oil three-phase existing simultaneously, whenrough structure is introduced into the solid surface [24].Water molecules are imbibed in the rough solid surface toform a barrier layer, which provides a strong repulsiveforce to the oil droplet, so solid surface can show theunderwater superoleophobic property [25]. In recentyears, the underwater superoleophobic materials andfundamental mechanisms have been developed [26−28],
1 State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University, Changchun 130012, China2 State Key Laboratory of Safety and Control for Chemicals, SINOPEC Research Institute of Safety Engineering, Qingdao 266101, China* Corresponding author (email: [email protected])
which present a new opportunity and promise to solvehigh efficiency oil-water separation [29,30], and someinorganic and polymer materials have been prepared onthe mesh membrane, but the idea superoleophobicmembranes with a strong separation ability, high se-paration efficiency, extensibility of the preparation pro-cess and long-term durability are still rather sparse andhighly required.
Metal organic frameworks (MOFs) are new porouscrystalline materials composed of inorganic metal centerscoordinated to organic linkers and thus possess theproperties of both inorganic and organic materials, whichare promising candidates for various applications, in-cluding gas storage, catalysis, sensors and water harvest-ing, etc. [31−39]. Particularly, zeolite imidazoleframeworks (ZIFs) as a subfamily of MOFs, exhibit var-ious topologies, diverse morphologies, robust chemicaland thermal stabilities [40,41]. Nowadays, MOFs andZIFs membrane have exhibited excellent performancesfor applications in gas and liquid separation [42,43], andattracted much attention of researchers working in thefields of materials science, chemistry and chemical en-gineering [44−52]. Several studies have shown that MOFmaterials can be prepared onto the mesh by in-situgrowth, such as JUC-150-coated and HKUST-1-coatedmesh membranes previously reported by our group,which exhibited excellent gas separation properties[53,54]. As known, ZIF-8 is one of the most popularMOFs, which has the advantages of outstanding chemicalstability, thermal stability, the readily available and cheapraw materials and straightforward synthesis. In the pre-sent work, we developed a stable ZIF-8-coated meshmembrane with micro-/nano architecture by a facilestrategy for high-efficiency oil-water separation. Com-pared to most of inorganic materials coated membranes,which usually have been fabricated by the chemical vapordeposition or hydrothermal synthesis, we successfullyconstructed a ZIF-8-coated mesh membrane with ex-cellent oil-water separation performance by simply im-mersing mesh in precursor solution under roomtemperature and atmospheric pressure (Fig. S1). The ZIF-8-coated mesh membrane showed underwater super-oleophobic properties, leading to high oil-water separa-tion efficiency over 99.99% and high water flux of10.2×104 L m−2 h−1, which can efficiently separate differ-ent oil and water mixtures driven by gravity. In addition,these membranes exhibited excellent thermal and che-mical stabilities. It is worth noting that this ZIF-8-coatedmesh membrane can realize large area fabrication andprovides potential applications in various oil-water se-
paration fields.
EXPERIMENTAL SECTION2-Methylimidazole (Hmim, 98%, Aladdin), zinc acetatedihydrate (Zn(Ac)2·2H2O, 99%, Aladdin), zinc nitratehexahydrate (Zn(NO3)2·6H2O, 98%, Sigma-Aldrich), cy-clohexane (AR, West Long Chemical Co., Ltd.), soybeanoil, diesel and pump oil were commercially available. Thestainless steel mesh (400 mesh/38 μm, 500 mesh/28 μm,800 mesh/10 μm, 540 Equipment Co., Xinxiang City,China. When the thickness of the ZIF-8 layer reached700 nm, the pore size of the mesh decreased only about1.4 μm) were cleaned with deionized water and ethanolunder ultrasonic.
ZIF-8 crystal seeds were fabricated as follows: 1.50 g ofZn(NO3)2·6H2O and 20 g of Hmim were added into90 mL of deionized water. The solutions were mixed andstirred for about 30 min at room temperature. The pro-duct was washed with ethanol by repeated centrifugation,and then dried in the oven at 80°C for 24 h. A seedssolution (1 wt%) was fabricated by dispersing the ZIF-8seeds into the deionized water. The seed mesh was pre-pared by immersing the pre-cleaned stainless steel meshin the seed solution for 5–10 min under the ultrasoniccondition, and then seed mesh was dried in the oven at120°C for 2 h. For secondary growth, the seeded meshwas immersed in a precursor solution consisting ofdeionized water, Zn(Ac)2·2H2O, and Hmim under am-bient temperature and pressure for 24 h. The molar ratioof the solution was Zn2+:Hmim:H2O =1:28:2222. Theprocess of secondary growth was repeated two times, andthe ZIF-8-coated mesh membrane was obtained. In thiswork, 500 mesh stainless steel mesh was used as the mainsubstrate to study the performance of oil-water separa-tion. The layered mixture of water and oil (50%, v/v) isslowly poured onto the prewetted membrane that wasfixed between two glass tubes. The separation was carriedout by the gravity of liquids. Then the permeated liquidwas collected in the glass bottle.
The X-ray diffraction (XRD) data were recorded on aPANalytical B.V. diffractometer using a Cu Kα radiation(λ=1.5418 Å). Scanning electron microscopy (SEM,EDXS) images were measured using JEOS JSM-6510. Oiland water contact angles were recorded at ambient tem-perature with the OCA20 machine (Data-Physics, Ger-many). The concentrations of oil in filtered water fordifferent kinds of oils were measured with the infraredspectrophotometer oil content analyzer (OIL- 460, Chi-na). The roughness was measured by Cypher S AtomicForce Microscopy (AFM). The adhesion force was re-
corded via a high-sensitivity micro-electromechanicalbalance system (Data-physics DCAT21, Germany).
RESULTS AND DISCUSSION
Synthesis of ZIF-8-coated mesh membraneZIF-8-coated mesh membrane was prepared by a simplesecondary growth method at ambient temperature andpressure, which could be readily scaled up (Scheme 1).XRD pattern of the ZIF-8-coated mesh membrane was inconsistent with the ZIF-8 simulated pattern, indicatingthat the highly crystalline ZIF-8 crystals could be grownon the stainless steel mesh (Fig. S2). In addition, we foundthat the Zn and N elements were uniformly distributedon the as-synthesized membrane by elemental mappinganalysis (Fig. S4).
Compared with the smooth bare stainless steel mesh,the layer of ZIF-8 nano-seeds was obviously formed onthe mesh by van der Waals interaction (Fig. 1a, b). SEMimages of the ZIF-8-coated mesh membrane demon-strated the smooth mesh surface was completely coveredby rough ZIF-8 coatings after the secondary growth (Fig.1c, d). The higher magnification SEM image exhibitedthat the surface of ZIF-8-coated mesh membrane wascomposed of continuous intergrown polyhedral nano-crystals with a dense, homogeneous and corrugatedgeometrical structure (Fig. 1e). From the cross-sectionalview, it can be seen that the ZIF-8 crystal layer was about700 nm thickness and there were no pinholes inside themembrane, and the ZIF-8 nanocrystals were exceedinglycompact and tightly attached to the substrate (Fig. 1f).These characteristics demonstrated the ZIF-8 was suc-cessfully fabricated on the stainless steel mesh through asimple method at ambient temperature and pressure. Andthe growth of nanostructured ZIF-8 crystals led to theformation of rich micro-/nano hierarchical surface, whichgreatly promoted the surface roughness of membrane.Similarly, ZIF-8 crystals completely covered the supportswith 400 and 800 mesh, showing the micro and nanohierarchical rough surface and there were no visible de-fects on membrane surface (Fig. S5).
In order to further research the surface properties of the
ZIF-8-coated mesh membrane, surface roughness ofmembrane was analyzed by AFM for a scanned area of2 µm×2 µm on the thread of stainless steel mesh. Theroot-mean-square (RMS) roughness was very accurate,which was often used to characterize the roughness. TheRMS roughness (Rrms) is calculated by the Equation (1):
R L Z x x= 1 ( ) d , (1)rms
L
0
2
where L is the evaluation length, Z(x) is the function ofsample height (Z) and sample position (x), which is usedto describe the surface profile. Obviously different surfacestructures of bare stainless steel mesh and ZIF-8-coatedmesh membrane can be observed in AFM images. While
Scheme 1 Schematic diagram of the preparation route of ZIF-8-coated mesh membrane with underwater superoleophobicity.
Figure 1 SEM images of ZIF-8-coated mesh membrane prepared onstainless steel mesh (500 mesh) by seeding and secondary growth pro-cess. (a) The bare stainless steel mesh and (b) the seeded stainless steelmesh with uniform ZIF-8 seeds. (c) The ZIF-8-coated mesh membraneand (d) a single ZIF-8-coated wire after secondary growth. (e) Themagnified image of ZIF-8-coated membrane surface, in which thehomogeneous intergrown polyhedral nanocrystals can be clearly ob-served. (f) The cross-sectional view of ZIF-8-coated mesh membrane.
the surface of bare stainless steel mesh exhibited smoothmorphology with a RMS roughness of about 8.66 nm(Fig. 2a), the surface of the ZIF-8-coated mesh membraneshowed a micro and nano hierarchical rough structures,and RMS roughness was about 68.67 nm (Fig. 2b). Theresult indicated that ZIF-8 crystals covered the stainlesssteel mesh resulting in a high surface roughness, whichwas conducive to ZIF-8-coated mesh membrane toachieve underwater superoleophobicity.
Wettability study of the ZIF-8-coated mesh membraneA ZIF-8-coated mesh membrane was immersed into thewater, showing superoleophobic performance (Fig. 3a),which was attributed to the micro and nanostructure onthe surface of the ZIF-8-coated membrane. When un-derwater oil contact angle (OCA) of a bare stainless steelmesh was about 85° (Fig. S6), the ZIF-8-coated meshmembrane showed outstanding underwater super-oleophobic behaviours with a high oil contact angle of150° (Fig. 3b) and an oil sliding angle around 8° (Fig. S7).The oil adhesion force was only about 13 μN, which in-dicated the membrane was not easily fouled by oil(Fig. S8). Through theoretical calculations, for solid/wa-ter/oil three phase system that possesses the rough sur-face, the CA can be exhibited using Cassie model, whichis shown in Equation [19,24]: cosθ'=fcosθ+f−1 (2), whereθ is the underwater OCA on a smooth surface, θ' is theunderwater OCA on a rough surface, and f represents thearea fraction of solid. When the area fraction becomessmaller, the contact chance decreases between oil dropletand solid surface, resulting in the larger OCA underwater.
As schematically shown in Fig. 3c, d, owing to the sharppolyhedral nanocrystals, our ZIF-8-coated mesh mem-brane has a rather rough surface, which means a verysmall area fraction as well as a larger OCA.
Due to the special wettability of ZIF-8-coated meshmembrane, a series of experiments on separation of oiland water mixtures were performed. As an underwatersuperoleophobic material, these mesh membranes hadbeen pre-wetted with water before the oil-water separa-tion. The cyclohexane and water (50%, v/v) mixture wasslowly poured onto the pre-wetted stainless steel mem-branes. The bare stainless steel mesh was used for oil andwater separation, which exhibited both water and oilpermeated through the bare stainless steel mesh com-pletely (Fig. S11a, b and Video S1). In other words, thebare stainless steel mesh has no ability of oil-water se-paration. Compared with the bare mesh, the water per-meated through the ZIF-8-coated mesh membrane withhigh flux, but the oil phase was rejected above themembrane (Fig. 4a, b and Video S2). Our ZIF-8-coatedmesh membranes exhibit the “water-removing” perfor-mance. The mechanism is the water pre-wetted ZIF-8-coated mesh membranes preferentially attracted watermolecules into the ZIF-8 micro and nanostructures andreduced the overall interfacial energy of the solid/water/oil three phase system, implying a very small area fractionof solid and exhibiting underwater oleophobic phenom-enon. The formed water barrier layer on a very roughsurface allows water to permeate through the membraneefficiently by gravity without any external force, whereas
Figure 2 3D and 2D AFM images of the bare thread of stainless steelmesh (a1, a2) and after coated with ZIF-8 (b1, b2).
Figure 3 Special wettability of ZIF-8-coated mesh membrane under-water. (a) The photograph of several oil droplets on the ZIF-8-coatedmesh membrane; (b) a contact angle image of an oil droplet on the ZIF-8-coated mesh membrane underwater; (c, d) schematic illustrations ofan oil droplet on a rough micro and nano architecture surface of ZIF-8-coated mesh membrane (dichloroethane dyed with Sudan III).
the oil phase is rejected completely. Similarly, the oil-water separation process of the ZIF-8-coated meshmembranes with 400 and 800 mesh were shown in VideosS3 and S4, respectively.
Encouraged by the simple preparation methods underambient temperature and pressure, the large-area fabri-cation of the ZIF-8-coated mesh membrane was easily
realized. As shown in Fig. 4c, the large-area ZIF-8-coatedmesh membrane (10.0 cm×10.0 cm) was placed on twotilted beakers, and then the oil-water mixture was pouredonto the membrane. The dyed red oil phase flowed overthe ZIF-8 membrane to the left beaker, while the purewater was collected in the right beaker (Fig. 4d and VideoS5). However, the bare stainless steel mesh could notseparate the oil-water mixture obviously (Figs S11c–f).Furthermore, as shown in Fig. 4e, the ZIF-8-coated meshmembrane (10.0 cm×10.0 cm) was folded into a “boat”and placed on a beaker. To evaluate the cleanup capabilityof ZIF-8-coated “boat”, several oil-water mixtures werecontinuously poured into the beaker through the mesh. Itcan be seen that all the dyed red oil successfully remainedin the “boat” while the water quickly permeated throughthe mesh, and no obvious flux decrease occurred (Fig. 4fand Video S6). Compared with preparation methods ofmost of the inorganic coated membranes, such as hy-drothermal synthesis, chemical vapor deposition or an-nealing method, the ZIF-8-coated mesh membrane canbe readily enlarged to separate a lot of oil-water mixturescontinuously and exhibits potential industrial application.
To quantitatively demonstrate the separation efficiencyof the ZIF-8-coated mesh membrane for the oil-watermixture, the residual oil content in the collected waterwas measured by an infrared spectrometer oil contentanalyser. The result indicated that high purity water withless than 4 ppm oil could be readily obtained through oil/water separation by using the ZIF-8-coated mesh mem-brane. Besides, ZIF-8-coated mesh membrane can beapplied to separate water from various oils includingdiesel, soybean oil, cyclohexane and pump oil, whichexhibited superior oil-water separation performance(Fig. 5a). To analyze the oil-water separation efficiency,the oil rejection coefficient R (%) was calculated by theequation: R=(1−C1/C0)×100% (3), where C0 is oil con-
Figure 4 Photographs of the oil-water separation process using (a, b)the ZIF-8-coated mesh membrane, (c, d) the large-area ZIF-8-coatedmesh membrane and (e, f) the ZIF-8-coated “boat” (cyclohexane wasdyed with Sudan III).
Figure 5 Oil-water separation performances of the ZIF-8-coated mesh membrane. (a) The separation efficiency and residual oil contents in thecollected water for various oils. (b) The influence of different mesh number on water flux and intrusion pressure of oil (calculated by cyclohexane).
centration in the oil-water mixture before separation, C1is oil concentration in collected water after separation.The membrane shows a high separation efficiency of over99.99% for various oils. And the water flux and intrusionpressure of oil were introduced to further study the se-paration properties. The water flux (F) was calculated bythe equation: F=VS/t (4), where V and t were volume andtime of water penetrating through the membrane, re-spectively, and S was the area of the membrane. The in-trusion pressure (P) values can be calculated using theequation: P=ρgh (5), where ρ is the density of oil, g is theacceleration of gravity, and h is the maximum height ofoil that the ZIF-8-coated mesh membrane can support.
The pore sizes of ZIF-8-coated mesh membrane wereeasily adjusted by the stainless steel mesh with differentmesh number. With the decrease of the mesh number,the pore size of the membrane increased. It was obviousthat the larger pore size of the ZIF-8-coated meshmembrane was more favorable for water permeation, butthe membrane cannot support too much oil, because ithad not enough surface tension. The higher oil intrusionpressure of 6,400 Pa and water flux of 10.2×104 L m−2 h−1
were achieved, respectively (Fig. 5b). The performances ofthe ZIF-8-coated membrane were among the best re-ported [12]. In addition, after the oil-water mixtures were
separated, the ZIF-8-coated mesh membrane can be easilyrecovered by simply washing the surface with ethanol,possessing good recyclability.
Stability and durability of the ZIF-8-coated meshmembraneTo explore the stability of the ZIF-8-coated mesh mem-brane, the high temperature and organic solvent re-sistance were evaluated. The thermal stability of the ZIF-8-coated mesh was examined by putting the as-preparedmeshes into the oven with different temperatures from100 to 200°C for 20 h. Moreover, the as-prepared ZIF-8meshes were immersed in various organic solvents in-cluding tetrahydrofuran (THF), N,N’-dimethylformamide(DMF), N-methyl-2-pyrrolidone (NMP), dichlorome-thane (DCM) and n-hexane for 20 h to evaluate thechemical stability. After high temperature and variousorganic solvents treatment, the XRD patterns of thesemembranes showed they were in consistent with the si-mulated pattern, suggesting the fully crystalline integrityof the coated ZIF-8 crystal layer (Figs S2, S3). The mor-phology of these treated ZIF-8-coated mesh membraneswere characterized by SEM, the results showed that ZIF-8nanocrystals remained compactly covered the mesh, andno visible cracks were formed on the membrane surface
Figure 6 Stability and recyclability of ZIF-8-coated mesh membrane (500 mesh). (a, b) Underwater oil contact angles (UWOCAs) of the ZIF-8-coatedmesh membrane after heating treatment under different temperatures and immersing in various organic solvents for 20 h. The inset: photos ofunderwater oil droplets (dichloroethane) standing on ZIF-8-coated mesh membranes after heating and immersing treatment. (c, d) Water flux andseparation efficiency for oil-water mixtures of ZIF-8-coated mesh membrane during the 10 cycles.
(Figs S9, S10). Analyzed by the CA measurements, theseZIF-8-coated mesh membranes still exhibited closed un-derwater superoleophobic properties (Fig. 6a, b). Andthen to study the recyclability of the ZIF-8-coated meshmembrane, the membrane was recycled 10 times. Theintrusion pressure of cyclohexane maintained a high va-lue and average height of oil column could reach 40 cmafter 10 times (Fig. S12). The separation efficiency forcyclohexane and water mixture had been above 99.99%,and water flux of ZIF-8-coated mesh membrane re-mained about 7.9×104 L m−2 h−1 during repeated experi-ments (Fig. 6c, d). Furthermore, in order to explore thestability of the ZIF-8-coated mesh membrane in water, itwas immersed in water for 20 days. SEM image revealedthat the ZIF-8-coated mesh membrane retained microand nano hierarchical rough surface (Fig. S13a), and theZIF-8-coated mesh membrane kept near underwater su-peroleophobic properties after 20 days (Fig. S13b).Moreover, there was no obvious change on the water fluxand separation efficiency for oil-water mixtures com-pared with the new membrane, which indicated that themembrane had long-term stability in the water (Fig. S14).In addition, the ZIF-8-coated mesh membrane was stablein solution from pH 6 to 12 for 20 h, and the oil-waterseparation efficiency remained about 99.99% (Fig. S15).These properties indicated that the ZIF-8-coated meshmembrane had excellent thermal and chemical stabilitiesand durability.
CONCLUSIONSIn summary, the ZIF-8-coated mesh membrane withunderwater superoleophobicity has been fabricated via afacile method under ambient temperature and pressure,which displays excellent oil-water separation properties.It can separate various oil and water mixtures driven bygravity, with outstanding separation efficiency over99.99% and water flux as high as 10.2×104 L m−2 h−1.Importantly, the membrane exhibits excellent stabilitiestowards high temperature and various organic solventsimmersion, durability and extensibility of the preparationprocess, which indicates the ZIF-8-coated mesh mem-brane will be a promising candidate for wastewatertreatment applications and clean-up of oil spills. And thiswork paves the way for further development of functionalapplications of MOF membrane materials.
Received 27 June 2018; accepted 27 August 2018;published online 19 September 2018
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Acknowledgements This work was financially supported by the Na-tional Natural Science Foundation of China (21571076, 21390394,21571079 and 61701543), “111” project (B07016), the Ministry of Sci-ence and Technology of SINOPEC (A381) and Open Projects of StateKey Laboratory of Safety and Control for Chemicals (SKL-038). Song M,Zhao Y, and Xue M are inventors of a Chinese patent(CN201810148543.6).
Author contributions Xue M, Zhao Y, and Qiu S conceived anddesigned this work. Song M and Xue M conducted the synthesis andanalyzed the data. Song M, Zhao Y, Mu S, Jiang C, Li Z, Yang P andFang Q performed the characterization. Song M, Zhao Y, and Xue Mwrote the paper. All authors contributed to the general discussion. SongM and Zhao Y contributed equally to this work.
Conflict of interest The authors declare no conflict of interest.
Supplementary information Supplementary data are available in theonline version of the paper.
Mingqiu Song is currently doing her research at the State Key Laboratory of Inorganic Synthesis and PreparativeChemistry, Jilin University, under the supervision of Prof. Shilun Qiu and Prof. Ming Xue. Her research interest mainlyfocuses on the synthesis and design of MOF membranes and their applications.
Yuxin Zhao obtained his BSc degree in chemistry of materials at China University of Petroleum (East) in 2009. Heobtained his PhD degree in chemical engineering and technology at China University of Petroleum (East) (2009–2014) inProf. Zifeng Yan’s group, with Best Undergraduate Thesis Award. In July 2015, Zhao joined SINOPEC Research Instituteof Safety Engineering to start his independent academic career. His research interest is in the synthesis of new classes ofmaterials and nanostructures, with an emphasis on their functionality.
Ming Xue received BSc (2003) and PhD (2008) degree from Jilin University (China) in Prof. Shilun Qiu’s group. Hejoined the University of Texas at San Antonio (USA) during 2007–2008 and 2014–2015 in Prof. Banglin Chen’s group.Currently, he works in the State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, Jilin University. Hisgroup focuses on the design and synthesis of multifunctional MOF materials and membranes for the applications inadsorption, separation and other advanced applications.
